Warnings are often ignored by developers unless you specifically force warnings to be compile errors (you can do this in most compiler). I work on TypeScript/C# code-bases and unless you force people to tidy up unused imports/using and variables, people will just leave them there.
This BTW can cause issues with dependency chains and cause odd compile issues as a result.
The point being conveyed is your experience is not representative of what commonly occurs. I have worked as a contractor in a number of different orgs both small, large, private and public and more often than not unless you force people to fix these things, they won't.
> Find better managers.
How about you and others with similar attitudes realise that the world isn't perfect and sometimes you have to work with what you got.
Do you think I haven't been looking for a new position? Most of the jobs in my area are going to be more of the same.
This BTW can cause issues with dependency chains and cause odd compile issues as a result.